Carlos Ghosn, Nissan's savior, is pushing the French automaker to get into gear

Smiling broadly and looking dapper in a powder blue shirt, pin-striped suit and bright red tie, Renault CEO Carlos Ghosn doesn't look like your typical corporate hatchet man. Back in 1999, however, Ghosn was dubbed the "samurai" and "cost killer" at Nissan Motor in Japan. As the newly appointed president, he began closing plants, slashing more than $20 billion in debt and eliminating 20,000-plus jobs to return the moribund company to profitability. Many observers--especially France's sometimes intractable unions--expected similar tough love in early February, when Ghosn unveiled his ambitious four-year plan for the European auto giant, which has had an increasingly...